JPS59180845A - Cassette shift driver in magnetic recording and reproducing device - Google Patents

Abstract

PURPOSE:To prevent the shaking or floating of a cassette holding stage at its working position by supporting a support shaft of a worm which gears with a worm gear movably in the axial direction and using a coil spring which transmits the prescribed axial moving power to said suport shaft. CONSTITUTION:When a cassette holding stage A is inhibited for its further move-down after it reaches the support surface, a worm gear 9 stops its revolution. However a motor 22 continues further its forward revolution. If a support shaft 20 is successively revolved owing to the over-run of the motor 22, the shaft 20 moves forth against the power of a coil spring 26 by a worm gear 19 revolving with gearing into a still a worm gear 9. Then the revolution of the motor 22 is stopped when the front edge of the shaft 20 turns off the 2nd switch 28. The backward moving power, i.e., the reaction of the compressed spring 26 is applied to the shaft 20. This power functions as the force which is applied to the engagement part between the worm 19 and the gear 9 to give the forward revolution to the gear 9. Thus the stage A is pressed to the support surface and fixed.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a cassette moving drive device for moving a cassette between an loading/unloading position and an operating position in a magnetic recording/reproducing apparatus such as a VTR that uses a so-called cassette cradle loading/unloading method. be.

In the above cassette front loading/unloading method, the cassette is inserted through one cassette slot provided on the front of the magnetic recording/reproducing device, and the cassette cradle containing the cassette is moved horizontally backward using the support frame. After that, it is moved vertically downward to reach the operating position, and when ejecting, it is moved in the opposite direction to return it to the insertion/removal position. In a magnetic recording/reproducing device using such a method, the general configuration of the first cassette moving drive device for moving the cassette as described above includes a worm gear as a drive wheel provided on one side of a support frame. The rotation of the worm gear is transmitted to movers such as rollers provided on both sides of the cassette pedestal through an intermediate transmission mechanism equipped with a drive arm, etc. Is the slider guide path K of the support frame? i=? By moving the cassette holder horizontally and vertically, the cassette holder is moved along the predetermined path.

The present invention is a drive device for moving a cassette as described above, in which the cassette pedestal can be firmly stabilized in the operating position so that it will not wobble or be lifted up. The invention is characterized by a coil spring that supports the support shaft of the A-arm that meshes with the worm gear serving as the driving wheel so as to be movable in the axial direction, and that applies a predetermined axial movement force to the support shaft. The spindle of the worm is moved in the axial direction against the coil spin link by overrun of the motor from the time when the cassette pedestal reaches the operating position and the worm gear stops, and the worm is moved by the spring reaction force. The worm gear is biased in the forward rotation direction (rotation direction in which the cassette pedestal is moved downward) through the worm gear.

Embodiments of the present invention will be described below with reference to the drawings.

A is a cassette pedestal, B is a support frame, and C is a chassis. The cassette holder A consists of a bottom wall 1 and left and right side walls 2 and 6, and is supported between the left and right side walls B, B2 of the support frame B, and is inserted from the cassette loading/unloading opening as shown in Fig. 4. The cassette D is accommodated and moved along both side walls B, , B2 of the support frame between an insertion/removal position j6 and an operating position. In FIG. 4(b), L indicates the support surface of the cassette pedestal A in the operating position. The movement guide device for horizontally and vertically moving the cassette pedestal A relative to the support frame B is well known and will not be described or illustrated. Further, the same applies to a tape operating mechanism such as a tape loading mechanism provided in the chassis C.

Both side walls B1 and B2 of the support frame are provided with a horizontally shaped groove 4 consisting of a horizontal portion 4a and a vertical portion 4b, and a horizontal portion 5a and a vertical portion 5b are provided on the outer surface of the support frame along the groove 4.
A horizontally shaped rack 5 consisting of the following is provided. On the other hand, on the cassette pedestal A, an interlocking rod 6 is rotatably attached to the lower surface of the bottom wall 1 so as to cross the bottom wall 1. Both ends of the interlocking rod 6 pass through the slots 4 of the support frame side walls B, B2 and protrude to the outside of the side walls, and pinions 7 and 8 as movers are respectively attached to the projecting ends of the supporting frame. 6, and the pinions 7.8 on both sides are engaged with the rack 5. Of these pinions 7.8 on both sides, the right pinion 8 is interlocked and connected to a drive mechanism, which is the main part of the drive device, which is installed on the right side wall B2 of the support frame, and serves as a drive pinion, and the rotation of this drive pinion 8 is controlled by an interlocking rod. 6 to the left driven pinion 7. That is, this embodiment of the apparatus employs a one-sided drive system in which the main mechanism is provided only on one side of the support frame B. ” The drive mechanism described in item 1 will be explained next.

Reference numeral 9 denotes a worm gear as a drive wheel, which is rotatably supported via a shaft 10 on the outer surface of the right side wall B2 of the support frame. 9 is provided with a rotatable cam 11, and this cam 1
1 and the worm gear 9, the gear 9 and the arc-shaped slot 12 provided in the gear 9, and the pin 1 engaged with the slot 12.
6 so that they can rotate freely within a certain range, and are connected by a compression coil spring 14 so that they can rotate together at all times. Reference numeral 15 denotes a door opening/closing lever, whose intermediate portion is pivoted to the right side wall B2 of the support frame, and whose one end contacts the outer peripheral surface of the cam 11 and the other end contacts the pivot end 16a of the cassette loading/unloading door 16. The door 16 is automatically opened and closed in response to the movement of the cassette pedestal A by the rotation of the lever 150 caused by the rotation of the cam 110.

In addition, further inside the cam 11, the base end of a drive arm 17 is rotatably pivotally attached to the periphery of the cam, and the distal end of the drive arm 17 is attached to the interlocking rod 6 that protrudes from the drive pinion 8. It is securely connected to the right end. In this way, 90 rotations of the worm gear are transmitted to the drive arm 17 via the cam 11, the rotational movement of the arm 17 drives the drive pinion 8, and at the same time, this driving force is transmitted to the driven pinion 7 via the interlocking rod 6. It is structured to convey. In this case, the drive arm 17 has its base end pivotally attached to the periphery of the cam 11 (substantially the worm gear 9) and its distal end pivoted to the interlocking rod 6, so that as shown in FIG. When the cassette pedestal A is in the loading/unloading position, the arm 17 is directed forward of the worm gear 9 and is accommodated within the circumferential range of the gear 9 to the maximum extent possible. According to such a drive arm configuration, when moving the cassette pedestal A, reference numeral 18 in FIG. 5 turns off a motor (described later) to stop the movement of the cassette pedestal A at the loading/unloading position. Due to the deviation in the off timing of the first switch 18, even if the cassette pedestal A reaches the front limit position, the
- If the worm gear 90 continues to rotate, the cam 11 remains stopped and only the worm gear 9 rotates within the slot 12 against the spring 14. Further, when the cassette D is pushed into the cassette holder A, the cam 11 and the drive arm 17 move freely against the spring 14, and the movement of the movement switch (not shown) causes the motor to be turned on by the free movement of the arm 17. Ru.

Next, 19 is a worm A'i 9 VC engaged with the worm in a horizontal position along the front-rear direction, 20 is a support shaft that rotates together with this worm 19, and this support shaft 20 is attached to the right side wall of the support frame. It is rotatably and axially movably supported by a bracket 21 protruding from the outer surface of B2. The rear part of the support shaft 20 penetrates the bracket 21 and projects rearward, and the protruding rear end of the support shaft 20 and the rotating shaft 22a of the motor 22, which is fixed to the rear frame B6 of the support frame B and can rotate in forward and reverse directions, are connected to the rear end of the support shaft 20. Goo! They are interlocked and connected by J23, 24 and a belt 25. A compression coil spring 26 is wound around the support shaft 20 between the pulley 26 of the support shaft 20 and the bracket 21, and the coil spring 26 applies a rearward tensile force to the support shaft 20. Therefore,
A thrust force in the direction of normal rotation of the worm gear 9 is always acting on the meshing portion of the worm 19 and the worm gear 9.

Reference numeral 27 denotes a stopper fixed to the support shaft 20, and the stopper 27 normally contacts the bracket 21 from the inside, thereby restricting the backward movement of the support shaft 20. Also, support
The front end of the 1l 120 is capable of protruding forward with respect to the bracket 21, and a second motor control switch 28 (shown in FIGS. 5 and 6) is provided facing the front end surface of the support shaft.
When the switch 28 moves forward, the switch 28 is pressed and turned off.

In such a configuration, until the cassette pedestal A moves horizontally rearward from the loading/unloading position and then moves vertically downward until it reaches the operating position, that is, the cassette pedestal support surface, the support shaft 20 of the worm 19 is The stopper 27 rotates in the state shown in FIG. 5 in contact with the bracket 21, and transmits the rotational force of the motor 22 to the worm gear 9 via the worm 19. When the cassette pedestal A reaches the support surface and is prevented from lowering further, the pinion 7.8 and the interlocking rod 6
Since the movement of the drive arm 17 and the cam 11 is stopped, the worm gear 9 also stops rotating, but the motor 22 continues to rotate normally, that is, overruns. When the spindle 2o continues to be driven to rotate due to the overrun of the motor 22, the spindle 20 moves forward against the coil spring 26 (') as shown in FIG. When the front end of the support 20 turns on the second switch 28, the motor 22 stops rotating.
A backward moving force is applied to the support shaft 20 as a reaction force of the compressed coil spring 26, and this force is
A force acts on the meshing portion of the worm 19 and the worm gear 9 in the direction of normal rotation of the gear 9. In this way, the worm gear 9 is fixed with a force in the forward rotation direction, and the cassette pedestal A is pressed against the support surface and fixed. As a result, the pedestal A is set in the operating position in a stable state without any unexpected wobbling or floating.

In addition, at the time of ejection, contrary to the above, after the worm 19 idles a predetermined amount and the support shaft 2o returns to its original position,
The normal meshing rotation of the worm 19 and the worm gear 9 is started, and the cassette holder A moves toward the cassette loading/unloading position.

- When using this device Q, which has the structure and function described above, the cassette holder A, that is, the cassette D, must be firmly and stably set in the operating position so that playback, recording, etc. can be performed properly. I can do it.

In particular, when using this device, the force for fixing the cassette pedestal A is stored in the meshing portion of the worm gear 9 and the worm 19, which are the drive source parts, so there is no risk of an imbalance in the fixing action between the left and right sides of the pedestal. , the pedestal fixing action is performed more reliably. In addition, the mechanism for fixing the pedestal is extremely simple, with only the worm support shaft 2DK coil spring 26 installed, and it only needs to be installed at one location in the worm gear mechanism, so the overall configuration is simple. The assembly cost and parts cost are low.

By the way, the present invention is not limited to the above-described embodiments, and can be implemented with various modifications as follows.

(B) In the above embodiment, the configuration is based on a one-sided drive system in which the main drive mechanism is provided only on one side of the support frame B. However, the present invention provides a configuration based on a unilateral drive system in which the main drive mechanism is provided on only one side of the support frame B. Of course, it is also applicable to a double-sided drive system in which a gear transmission mechanism is provided, these are connected by a fixed transmission shaft, and the rotational force of the worm gear is distributed to both sides.

(b) - In the above embodiment, the pinion 7 and the mover are
Although the pinion 7.8 is used, a roller or a slide may be used in place of the pinion 7.8, and this may be used in the guide groove for rolling or sliding.

(c) The specific configuration of the intermediate transmission mechanism that transmits the rotation of the worm gear to the mover can be modified in various ways, such as using a drive arm with a fixed fulcrum that performs a simple rotational movement.

) The rotating shaft 22a of the motor 22 and the worm support tlQl
For the interlocking connection means of +20, it is possible to adopt a gear transmission mechanism or the like in addition to the belt transmission mechanism of the above embodiment.

Alternatively, the motor rotation shaft 22a and the worm support shaft 20 may be disposed on the same axis, and they may be connected removably through a direct connection, a screw, or a joint. (E) In the above embodiment, the motor 22 overrun,
Although the configuration is such that control is performed by the support shaft 20 and the switch 28, this control means may be provided in a portion unrelated to the support shaft 20. Alternatively, it is also possible to perform timer control in place of such a side-by-side switch.

As described above, according to the present invention, the cassette pedestal can be set firmly and stably in the operating position without accidentally wobbling or lifting, and the structure is simple and the cost is low. However, the cassette pedestal fixing function is highly reliable.

[Brief explanation of the drawing]

The figures show an embodiment of the present invention, in which Fig. 1 is a perspective view with the cassette movement guide mechanism etc. omitted, Fig. 2 is a perspective view seen from a different direction from Fig. 1, Fig. 6 is an exploded perspective view, and Fig. 4 Figure (a) is an enlarged side sectional view when the cassette holder is in the cassette loading/unloading position, (b) is an enlarged side sectional view when the cassette holder is in the same operating position, and Figure 5 is the main part before the fixing action of the cassette holder starts. FIG. 6 is an enlarged side view in the same operating state. A cassette pedestal, B support frame, B1. B2 Both side walls of support frame, 5 Rack as mover guide path,
7, 8...Both sides mover, 9 Worm gear, 19 Worm, 20 Support shaft of the same worm, 21 Same sentence IQl+
Supporting bracket, 22...Motor, 22a...Motor rotating shaft, 26...Coil spring. Patent applicant Imaike Seiko Co., Ltd.

Claims (1)

[Claims] 1. A cassette inserted through the cassette slot provided on the front of the magnetic recording/reproducing device is housed in a cassette cradle, and during operation, the cassette cradle is moved horizontally backward along the support frame and then vertically. In a magnetic recording/reproducing device, the cassette pedestal is moved downward to reach the operating position, and when ejecting, the cassette pedestal is moved in the opposite direction to the loading/unloading position, and movers are provided on both sides of the force center pedestal. In addition, a slider guide path consisting of a horizontal portion and a vertical portion for guiding the movement of the slider on both sides is provided on both side walls of the support frame, and the slider on both sides is connected to a driving worm gear provided on one side of the support frame. The support shaft of the worm is interlocked with the worm gear, and the supporting shaft of the worm is interlocked with the rotating shaft of the motor, so that the worm and the worm gear are connected to each other so that the motor rotates in the normal direction during the above operation, and reversely rotates during the ejection. The cassette moving drive device is configured to move the cassette holder along the horizontal and vertical movement paths by transmitting the information to the both side movers through the worm and the support frame. In addition to being supported so as to be movable in the axial direction,
A coil spring is provided to apply a predetermined axial movement force to the support shaft, and from the time when the cassette pedestal reaches the operating position and the worm gear comes to rest, the motor overroller moves the support shaft above the 1. A drive device for moving a cassette in a magnetic recording/reproducing device, characterized in that the cassette is moved in an axial direction against a coil spring, and the spring reaction force urges a worm gear in the normal rotation direction via a worm.